The Diasio D962R blends a chassis made in the United States with an engine built in Japan and a transmission made in the United Kingdom. It’s a convincing combination with the numbers to prove it. The engine makes 240 horsepower at the wheels. The car weighs just 1,578 pounds — and that includes the driver. That’s just 6.5 pounds per unit of horsepower, which is, well, respectable.

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There also is a practical side to Sam Mangiameli’s Diasio D962R, too. First it runs on 15-inch tires, the largest diameter before rubber becomes expensive. Why do you think stock cars still run that size? No matter, though, because the car is a genuine featherweight, it is easy on tires.

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“It doesn’t really degrade tires like a 3,500-pound Corvette would or something like that,” said Mangiameli, a NASA Central member from Omaha, Neb.

Mangiameli and his father bought the car second hand last year and used it for track days in preparation for 2013. Mangiameli is now racing it in Super Unlimited class. When we spoke to him in mid-July, he had just returned from High Plains Raceway where he broke the track record, then went out and beat his own lap time.

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“It was an awesome experience,” he said. “That was my first time ever running on that track, and the first time out was in the rain, and we went out there and had a great battle with the Panoz and the Porsches.”

Mangiameli started out in racing on dirt ovals in a kart, but he has always had his eye on road course racing, and he in fact is determined to make sports car racing his career. He is aiming for the American LeMans series. His plans are to drive the Diasio to a point in his amateur career where he can make the leap into the pros. The car itself is just the tool to take him there.

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For starters, it’s a dedicated race car, not a production car adapted for racing. The Diasio Car Company is based at the Putnam Park Road Course in Whitestown, Ind., but the cars themselves are manufactured in Palm Beach, Fla. The chassis begins with the cabin structure, which includes the main hoop and roll cage and the side pods, which house the fuel tank and the cooling components.

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For power, Mangiameli’s Diasio uses a naturally aspirated Mazda Renesis rotary engine, but a turbo model also is available — you know, if 6.5 pounds per horsepower isn’t stout enough for you. The transmission is a Hewland sequential six-speed with reverse gear. The engine and transmission serve as stressed members to which the rear push rod suspension components attach.

“It’s been a great car. It handles phenomenally,” Mangiameli said. “I’ve been to Mid-America Motorplex, Topeka and we just got back from High Plains Raceway this past weekend, and it’s been a huge learning experience. It’s taught me a lot.

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Downforce? Yes, it has that, too. From the overall shape of the car to the splitter and canards up front, the louvers atop the front fenders to the massive rear wing and end plates, the D962R sticks.

“It handles differently than any other car I’ve ever driven, especially in traffic,” Mangiameli said. “It holds its own even when it’s in the wake of another car. It doesn’t lose any handling or any downforce. It’s taught me a lot about different driving styles. Its definitely more responsive than any other car I’ve ever driven, unlike being out there in a Corvette or a Porsche where there’s a lot more weight transfer. Just the lighter weight of this car and the aero package and the suspension setup, it really just handles almost like a little slot car.

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“It turns wherever you want to go,” he added. “You can put this car anywhere and it’ll do it. It really takes a big mistake to get the car out of shape or lose control of it.”

Because it was designed as a racecar, everything is a snap to get to and engineered to be serviced easily. Camber changes are as simple as installing shims, but the car typically stays where it’s set unless he goes off big time or slams a curb the wrong way. For service work that is beyond the capabilities of Mangiameli and his dad, they take it to Jesse Prather Motorsports in Topeka, Kan.

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“I’ve raced now in all conditions, from cold to hot to rainy and it’s been a very good, consistent car,” he said. “It’s taught me a lot with car control and different driving styles. It’s a whole new world of racing, with the way road course racing works compared with oval racing.”

It’s definitely the right tool for the job. All Mangiameli needs to do now is drive it to the doorstep of the American LeMans series.

Sam Mangiameli’s 2006 Diasio D962R Sports Racer


1,578 lbs. with driver


Mazda Renesis rotary, 240 whp.


Front: Koni coil over, double adjustable.

Rear: Koni push rod, double adjustable


Hoosier RS


Front: Wilwood, steel ventilated rotors

Rear: Wilwood, steel ventilated rotors

Data system:

RLC race analyzer with Motech ECU


Creative Hair Design Motorsports, Sterling Financial Advisors LLC
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Image courtesy of Brett Becker


  1. You need to return in the car back to its roots here in Indianapolis Indiana where Diasio originally built the cars and a track to test them on just west of Indy and at that time he offered an engine from a Yamaha motorcycle of only 150 horsepower that lapped everything on Putnam Park , a track that Diasio built a 1.5 mile , ten turns asphalt road course … Take your Diasio to Putnam Park for a lap day and be honored by all you meet at the track and will be an adventure for you to remember to add to all your fun …D962R has to be the ultimate fun and serious car today ! And there are those of us who take advantage of registration laws and equip such off road vehicles with dot approved safety and driveability necessary to be street legal and take these baby Porsche’s to the street for causing nothing less than chaos and mayhem

    • Hello Charles,
      Can you elaborate as much as possible on your experience of what it takes to make a D962R street legal? Any internet D962R street build threads you could reference?

      I understand the very good reasons why doing this with a car designed strictly for racing is in no way responsible, safe, or recommended, but I’d really like to know anyway.

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